/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.log4j.chainsaw;

import java.io.EOFException;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import org.apache.log4j.Logger;
import org.apache.log4j.spi.LoggingEvent;

/**
 * A daemon thread the processes connections from a
 * <code>org.apache.log4j.net.SocketAppender.html</code>.
 * 
 * @author <a href="mailto:oliver@puppycrawl.com">Oliver Burn</a>
 */
class LoggingReceiver extends Thread {
	/** used to log messages **/
	private static final Logger LOG = Logger.getLogger(LoggingReceiver.class);

	/**
	 * Helper that actually processes a client connection. It receives events
	 * and adds them to the supplied model.
	 * 
	 * @author <a href="mailto:oliver@puppycrawl.com">Oliver Burn</a>
	 */
	private class Slurper implements Runnable {
		/** socket connection to read events from **/
		private final Socket mClient;

		/**
		 * Creates a new <code>Slurper</code> instance.
		 * 
		 * @param aClient
		 *            socket to receive events from
		 */
		Slurper(Socket aClient) {
			mClient = aClient;
		}

		/** loops getting the events **/
		public void run() {
			LOG.debug("Starting to get data");
			try {
				final ObjectInputStream ois = new ObjectInputStream(mClient
						.getInputStream());
				while (true) {
					final LoggingEvent event = (LoggingEvent) ois.readObject();
					mModel.addEvent(new EventDetails(event));
				}
			} catch (EOFException e) {
				LOG.info("Reached EOF, closing connection");
			} catch (SocketException e) {
				LOG.info("Caught SocketException, closing connection");
			} catch (IOException e) {
				LOG.warn("Got IOException, closing connection", e);
			} catch (ClassNotFoundException e) {
				LOG.warn("Got ClassNotFoundException, closing connection", e);
			}

			try {
				mClient.close();
			} catch (IOException e) {
				LOG.warn("Error closing connection", e);
			}
		}
	}

	/** where to put the events **/
	private MyTableModel mModel;

	/** server for listening for connections **/
	private ServerSocket mSvrSock;

	/**
	 * Creates a new <code>LoggingReceiver</code> instance.
	 * 
	 * @param aModel
	 *            model to place put received into
	 * @param aPort
	 *            port to listen on
	 * @throws IOException
	 *             if an error occurs
	 */
	LoggingReceiver(MyTableModel aModel, int aPort) throws IOException {
		setDaemon(true);
		mModel = aModel;
		mSvrSock = new ServerSocket(aPort);
	}

	/** Listens for client connections **/
	public void run() {
		LOG.info("Thread started");
		try {
			while (true) {
				LOG.debug("Waiting for a connection");
				final Socket client = mSvrSock.accept();
				LOG.debug("Got a connection from "
						+ client.getInetAddress().getHostName());
				final Thread t = new Thread(new Slurper(client));
				t.setDaemon(true);
				t.start();
			}
		} catch (IOException e) {
			LOG.error("Error in accepting connections, stopping.", e);
		}
	}
}
